Document Type : Original Research Paper
Authors
1 Ph.D. Student, Department of Geology, Islamic Azad University, Science and Research Branch, Tehran, Iran.
2 Professor, Department of Geology, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran.
3 Associate Professor, Department of Geology, Faculty of Sciences, Tehran University, Tehran, Iran.
Abstract
After Early Cimmerian orogenic stage, due to marine transgression, the Nayband Formation Norian_Rethian (Upper Triassic) in age deposited in the Central Iran Zone. Because of transforming of aragonite and high Mg calcite into low Mg calcite during diagenesis, recognition of original carbonate mineralogy based on petrographic studies is difficult. In this research, original carbonate mineralogy and type of carbonates (tropical, temperate and polar) of the Nayband Formation in Darbidkhoon, Tarz, Gitry and Kuhbanan stratigraghic sections have been studied using geochemical evidences. The trace elements (Na, Sr, Fe, Mn) and isotopes (and) data of the Nayband Formation carbonates is located inside or close to the aragonitic tropical Fahlian Formation (Lower Cretaceous), the Ilam Formation (Upper Cretaceous), the Kangane Formation (Lower Triassic) and the Mozduran Formation (Upper Jurassic) limestones, because of aragonitic original carbonate mineralogy. The results of elemental and isotopic analysis correlate with the petrographic evidences and paleogeographic map of the Upper Triassic.
Keywords
)